Status (U) command

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Description (see command description format info here)


Function:Returns additional DS status information


Can be issued through:Network (broadcasts OK, login not required); serial port


Command format:U[v], where v is an optional "command version" parameter (decimal number up to 255, when omitted defaults to 1). Command version is only recognized in firmware V3.54+


Possible replies (network):Addd.ddd.ddd.ddd/ppppp/eee/ttt/ccc/sss/fff/r/sdfpb/RCTS[/iii.iii.iii.iii], where

       ddd.ddd.ddd.ddd- IP-address of the network host with which the data connection is (was/ to be) established;

       ppppp- data port number on the network host with which the data connection is (was/ to be) established;

       eee- total number of characters in the Ethernet-to-serial buffer;

       ttt- capacity of the Ethernet-to-serial buffer;

       ccc- number of committed characters in the serial-to-Ethernet buffer;

       sss- total number of characters in the serial-to-Ethernet buffer;

       fff- capacity of the serial-to-Ethernet buffer;

       r- current baudrate (same numbering is used as in the Baudrate (BR) setting);

       s- serial port state: '*' (closed), 'O' (opened);

       d- serial port mode: 'F' (full-duplex), 'H' (half-duplex);

       f- flow control: '*' (disabled), 'R' (RTS/CTS flow control);

       p- parity: '*' (none), 'E' (even), 'O' (odd), 'M' (mark), 'S' (space);

       b- bits per byte: '7' (7 bits), '8' (8 bits);

       R- current state of the RTS (output) line: '*' (LOW*), 'R' (HIGH*);

       C- current state of the CTS (input) line: '*' (LOW*), 'C' (HIGH*);

       T- current state of the DTR (output) line: '*' (LOW*), 'T' (HIGH*);

       S- current state of the DSR (input) line: '*' (LOW*), 'S' (HIGH*);

       [V3.54+] iii.iii.iii.iii- only returned when command version parameter of >1 is supplied- IP-address of the DS on the PPPoE link.


Possible replies (serial):Addd.ddd.ddd.ddd/ppppp[/iii.iii.iii.iii] (see field description above)


First introduced:Earlier than "baseline" V3.14/V3.51, functionality extended in V3.54


See also:Network programming, Serial programming, Data routing, Serial-to-Ethernet data routing, PPPoE




Status command returns additional information about the status of the DS. In conjunction with the Echo (X) command it can be used to obtain extensive information about the state of the DS.


The following data is returned:


ddd.ddd.ddd.ddd and ppppp fields. IP-address and port number of the network host with which the data connection is (was/ to be) established. IP-address in this field shows the following:


After the power-up the fields returns the IP-address and port defined by the Destination IP-address (DI) setting and Destination Port Number (DP) setting;


If these default values are overridden by the Destination IP-address (DI) parameter, Destination Port Number (DP) parameter, or Establish Connection (CE) instruction, then the fields show new overriding values;


While the data connection is established and after it is closed (aborted) the fields show the IP-address and port of the network host with which this connection is (was) established. Notice that this may be different from the above- if the DS has accepted an incoming connection.


eee and ttt fields show the total number of data bytes in the Ethernet-to-serial buffer and the capacity of this buffer. Capacity information is included because the buffer size is different for different models of the DS.


ccc, sss, and fff fields show the number of committed bytes in the serial-to-Ethernet buffer, total number of bytes in this buffer, and the buffer capacity. Again, buffer capacity is included because it differs depending on the DS model.


r, d, f, p, and b flags show current serial port setup. This information is useful because on-the-fly commands (network-side parameters and instructions) can change serial port communications parameters at any time.


d flag reflects whether the serial port is in the half-duplex or full-duplex mode. This data may be of interest when the Serial Interface (SI) setting is 2 (auto) and you need to verify what mode the DS has assumed at startup.


R, C, T, and S flags reflect current status of the RTS, CTS, DTR, and DSR lines of the serial port. This information may be useful in debugging communications problems between the DS and the attached serial device.


[V3.54+] iii.iii.iii.iii field- only returned when command version parameter of >1 is supplied- IP-address of the DS on the PPPoE link. As explained in PPPoE the DS negotiates a separate and different IP-address for PPPoE communications.



Optional command version parameter has been introduced in firmware V3.54. Command version is a decimal number (up to 255). When command version is omitted it is assumed to be 1. Earlier firmware releases do not support this parameter and will simply ignore it (result will be the same as having command version set to 1). When command version of 2 or higher is supplied Status command returns an additional iii.iii.iii.iii field.



Example #1: supposing U command returns the following reply**:


-->DS:        U

DS-->:        A192.168.100.90/37150/0/8192/0/3/8192/5/OFR*8/R*TS


This means that the data connection is (was/ to be) established with the network host at, port number 37150. No data is currently in the Ethernet-to-serial buffer, buffer capacity is 8192 bytes. No committed data is in the serial-to-Ethernet buffer, there are 3 bytes of  (uncommitted) data there, and the total capacity is 8192 bytes. The baudrate is 38400, serial port is opened, uses full-duplex mode. RTS/CTS flow control is enabled, parity is set to none, data is 8 bits/byte. RTS, DTR, and DSR lines are in the HIGH* state, CTS line is LOW*.


Example #2: here is a command with version parameter**:


-->DS:        U2

DS-->:        A192.168.100.90/37150/0/8192/0/3/8192/5/OFR*8/R*TS/


In this reply an additional field is present. This field shows that current IP-address on the PPPoE link is


When issued through the serial port, the Status command returns less data. The primary use of the serial Status command is to let the attached serial device inquire the IP-address and port number of the network host with which the connection is (was/ to be) established (as well as current "PPPoE" IP-address). This may be used by the serial device, in conjunction with the modem commands (serial-side parameters and instructions) to control and monitor data connection establishment and termination by the DS.


* HI and LOW states are described with respect to the serial ports of DS100R, DS100B, DS203. For EM100, EM120, EM200, EM203(A) the signaling is exactly opposite.


** Encapsulation characters such as IEC, STX, CR, and the command ID field are not shown.